everything working in docker container except flash messages

Dockerfile

Frontend/static/net.png

Frontend/static/preview_net.png

Frontend/static/process_net.png

Frontend/static/styles.css

Frontend/static/user_manual.pdf

Frontend/templates/aboutus.html

Frontend/templates/case.html

Frontend/templates/index.html

Frontend/templates/info.html

Frontend/templates/preview.html

Frontend/templates/result.html

Frontend/templates/start.html

backend/__pycache__/businessprocess.cpython-311.pyc

backend/__pycache__/case.cpython-311.pyc

backend/__pycache__/dqn.cpython-311.pyc

backend/__pycache__/environment.cpython-311.pyc

backend/__pycache__/eventlog.cpython-311.pyc

backend/__pycache__/petrinet.cpython-311.pyc

backend/__pycache__/simplesimmodel.cpython-311.pyc